A medical balloon includes an outer layer and an inner layer. The outer layer has a surface texture or formation, such as a scoring element. The inner layer is made of a reflow material which during production of the balloon from a raw tubing will soften and flow into internal recesses in the outer layer, thereby filling these recesses and providing support to the outer layer formations so as to avoid flattening of these formations during use of the balloon. The balloon can be manufactured in a single formation step from raw tubing having the outer and inner reflow layer coextruded.